Sort Display List Objects Based on Y Depth

Thanks to the example on this page:

http://www.senocular.com/flash/tutorials/as3withflashcs3/?page=2

function sortChildrenByY(container:MovieClip):void {
 var i:int;
 var childList:Array = new Array();
 i = container.numChildren;
 while(i--){
  childList[i] = container.getChildAt(i);
 }
 childList.sortOn("y", Array.NUMERIC);
 i = container.numChildren;
 while(i--){
  if (childList[i] != container.getChildAt(i)){
   container.setChildIndex(childList[i], i);
  }
 }
}

sortChildrenByY(this);